A picker assembly that is used for picking individual pieces of material, such as seed potatoes from a hopper, and carrying them to a position where they are stripped off the individual picks or spears. As shown, the pieces are dropped through a suitable chute to a furrow being prepared by a planter. The picks or spears are carried on an arm and have conical outer surfaces that fit in matching conical bores and are locked in place by applying axial force to the picks. The picks are secured so they do not tend to work loose during use.
The pick assemblies for potato planters are well known and comprise a movable arm carrying the picks and a stationary arm. The arms are mounted on a rotating wheel and the movable arm carrying the picks will move from a position where the picks protrude through an opening in the stationary arm for engaging a seed potato, to a position where it retracts from the stationary arm and the stationary arm acts as a stripper to remove the potato.
In the prior art, rotating wheel potato planters have been well known, which include arms that carry picks, or spear-like sharpened columns or spears that will pierce or penetrate a potato as the wheel moves through a potato supply, with each arm picking up one seed potato and carrying it with the wheel in its path of rotation to a second position where the seed potato will be dropped. The arms that are used include a stationary arm, and a movable pick arm that supports the pick, with the pick protruding through an opening in the movable arm. As the arm set moves through the supply of seed potatoes, the pick pierces a seed potato. When the wheel on which the arms are mounted rotates to the position where the seed potato should be dropped for planting, the movable pick-carrying arm is retracted and the stationary arm of that set acts as a stripper to strip the seed potato from the pick. The movable pick arm then moves back to its position (as it enters the potato supply) with the picks protruding from the stationary arm as the arm set enters the seed potato supply so that the arm set will again pick up a seed potato, which usually is a section of a complete potato.
Various attempts have been made to maintain the picks securely held in the movable picker arm, but the picks continue to loosen and prematurely wear. For example, one prior pick was passed through a straight hole in the arm and it had a countersunk head held in position by a retainer bearing on the pick head with an axial force to seat the countersunk head. This arrangement failed to maintain the pick tightly in position during use. A straight cylindrical hole where the pick head is held down with a set screw that in turn is supported on a bar or cross member carried on the arm and passing over the pick has also been tried but has not proved satisfactory. Retainers of various kinds have been used, but generally they have failed to hold the pick tightly and securely, and yet allow it to be removed relatively easily for replacement when needed.